chore: update README.md to emphasize the importance of importing styles (#260)

* initial draft of README me message to emphasize importance of included styles.css file

* remove accidentally added characters

* repositioned style message in code snippet

* fix: remove extraneous whitespace and use more relevant advanced styling link

Author: Robbie Nohra

README.md

@@ -22,8 +22,11 @@ yarn add react-base-table
 ```js
 import BaseTable, { Column } from 'react-base-table'
 import 'react-base-table/styles.css'
-
-...
+// Important: if you fail to import react-base-table/styles.css then 
+// BaseTable will not render as advertised in the included examples.
+// For advanced styling see link below:
+// https://github.com/Autodesk/react-base-table#advance
+ ...
 <BaseTable data={data} width={600} height={400}>
   <Column key="col0" dataKey="col0" width={100} />
   <Column key="col1" dataKey="col1" width={100} />